Process and machine for thickening pulp



J1me 1929- A. J. HAUG ET AL PROCESS AND MACHINE FOR THICKENING PULP Filed Oct. 1927 4 Sheets-Sheet June 1929- A. J. HAUG ET AL PROCESS AND MACHINE FOR THICKENING PULP 1927 4 Sheets-Sheet Filed Oct. 4

June 18, 1929. A. J. HAUG ET AL PROCESS AND MACHINE FOR THICKENING PULP Filed Oct. 4, 19.27 4 Sheets-Sheet III/Ia ,7 22 L/YVg/VTORS gag A 7" ToRA/E/ 40 tion, showing a pulp'thickeriihg machine conconducted 1nto the drum through an inlet Patented June 18, 19 29.

UNITED STATES PATENT OFFICE.

ANTON .1. HAUG- AND nrc'izann .1. mus, or NASHUA, NEW immrsnnui; earn menam) .r. naueassicnoaro sam ANTON J. rune.

' Pnocass AND MACHINE roa THIcxENiNG PULP.

. Application ni i October 4, 1927. Serial No. 228,887.

This invention relates particularly to processes of';and machines forperformmg the various screening orstraining operations showing details of the construction of the I to which paper pulp is subjected in the course of preparing it forthe paper makin operation. The invention will be herein isclosed 'as embodied in a pulp thickening machlne, although it is contemplated that some features of the invention may be applledto other uses, and the term pulp is therefore used in a generic sense to include other materials which the machine is adapted to handle.

Pulp thickeners are used in the" paper male. ing industry to strain out surplus water 1n which the solid constituents of the pulp are suspended and thus to concentrate-the pulp more or less. The present invention aimsto devise a machine which will perform this operation rapidly and efiiciently; will have a lar e'capacity in proportion to its size, and will e economical to manufacture. lanes pecially important feature of the invention resides in the construction-of the strainingdrum. The invention also aims to improve the means for removing the thickened pulp from the straining surface with a view to effecting such removal continuously, providing for the proper-control of the t h1 ckness of the layer of pulp on the straining surface, and avoiding any possibility of injury to said surface.

The nature of the invention 'will be readily understood from the followin description when read in connection .with t e accomwill be particularly pointed out ,inthe appended claims. g

In the draxvings,

' Figure l is a view, partly in side elevation I dilute, ,contalnlng only a small ercentage of and partly in longitudinal vertical cross-secstructed in accordance with this invention Fig. 2 is a plan view, partly 1n cross sectlon, of the machine shown in Fig. l but 5 showing it equipped with a mechanism for 5 Fig. 6 is a longitudinal, cross-sectional.

panying drawings, and the novel features.

view through one side of the drum shown in Fig. 5; and 1 Figs. 7' and 8 are cross-sectional views drum.

Referring first to Figs; 1; 2 and 3, the machine .there' shown-comprises a rotar ,strainingdrum, indicated in general at 2, t is drum being mounted on one end of ahorizontal shaft 3 which is supportedin bearings 4-4 mounted on a base 5. The shaft 3 is provided with a pulley 6 by' means' of which the machine may be belted-to any convenient source of power. A casing encloses the drum 2 and comprises end pieces 7 and 8, respectively, both mounted on the base-5, and a'circumferential' section" 10 which may be removed to permit access to the drum 2. Preferabl the two end pieces 7-and 8 are divided horizontally for convenience in manufacture and assembling.

receive a flange It on the casing member 8.

The ring 13 and head 12 are rigidly connected togetherby parts which will be described later in detail,- and the straining surface 15 is lo cated between the ring and head.-j'jThis straining surface or sieve is-of circular form v in cross-section and it may b'eeither ta eredor W cylindrical, 'but.. preferabl ii pared, as clearly shown in I end of the drum being closed by the head 12,

is .sli tly a ig. 1,1516 larger and the smaller end being-open.

The pulp to be thickened usually is very fibre or other solid matter, an th'is pu p is spout 16 which issupported 1n the end piece 8 of the casing. The spout is curved as clearly shown in Figs. 1, 2-an'd 3, and is provided with a substantiallyhorizontal dis- .charge outlet at its lower end. The stock to be -thickened may flow into the intake spout from a head box orany other suitable arrangement, but usually runs-in at a relatively low velocity.

In order to control the deliveryof this ing the gate to control the width of the aperture through which the pulp is discharged. Preferably this gate is in the form of a half cylinder, as shown in thedrawings, and 1s secured to a horizontal shaft-18 which is supported in two bearings 202O at the opposite ends of the discharge opening of the spout. This shaft also projects throughthe end piece 8 of the casing, as best shown'in Fig. 4.- Secured to the outer end of this shaft is a sector. 21 having a slot 22 therethrough to receive a bolt 23 which is threaded into the casing member 8. This construction permits the adjustment of the gate 17 from a oint out side the casing and while the mac line is in operation, the bolt 23 serving to hold the gate in its adjusted position. I

Preferably the discharge end of the inlet spout is curved inthe direction of revolution of the drum, as shown in Fig. 3, and-the gate 17 should be so adjusted that when the machine'is in operation a layer of' 'pulp of suitable thickness flows 'continuously"onto the straining surface 15 in the directionof revolution of said drum. The drum should be revolved at such a speed as to create a very I substantial centrifugalforce which throws the water in the pulp forcibly through the straining surface and into .the casing where it drains out almost immediately through an outlet spout 24, Fig. 3, no part of the straining'surface preferablybeln submerged in water at any time. The soli constituents of the pulp collect in athlckened mass on the inner side of the straining surface. Preferably this-surface or strainer 15 consists ofwire fabric, and inorder to avoid any possibility of injury to it, a novel arrangement has been provided for moving the thickened pulp acrossthe surface of the strainer and eject ing it from the drum.

As shown, this apparatus includes a spray pipe 25 supportedin the casing member 8 and-extending into the drum closely ad aeentto'the lower side thereof. This pipe is designed to be connected with a supply of water or other fluid under'pressure through a valve 26, Fig. 1, and itis provided inside the drum witha series of outlet aperturesarran ed to direct jets of water against. the .thic 'ened pulp, these jets being soinclined that they act on the pulp to forceit'aeross the strainor outlet end thereof. The velocity of the water or other fluid in the ets which perform this ejectin operation can be controlled by adjusting t e valve 26. This'arrangeme'nt thus effectually dischar es the pulp from the drum while avoiding he use of mechanical scrapers which'might injure the wire fabric.

The spra ing-mechanism just described moves the t ickenedpulp into the range of operation of a scraper 27; Figs. 1, 2 and 3, which is secured to the casing member 8 and is provided with an inclined edge spaced slightly from the innersurfaces of thering 13, previously referred lo, and another ring;

28 which lies between the ring 13 and the Y screen 15. The rotarymotion of the drum carries the thickened pulp against this scraper which. lifts it and "diverts it outwardly toward the discharge chute 30, Fig. 1. Some of this pulp will be thrown outwardly into the-chamber 31, Fig. 1, which is formed in the outer part of the casing 8, and this pulp.

will be removed and discharged by one or more scrapers 32 which are secured to ring 13.

As above stated, a tapered construction of strainer drum is preferred, one reason being that this shape avoidsjhe tendency of the stock to move toward the discharge end of the drum before it has come sufficiently under the control of centrifugal force. It thus 1 permits a more accurate control of the discharging movement of the'thickened pulp.'

a guide 33 so that it can move longitudinally,

inay

and a lever 34 is connected to the spray pipe,

37 in one end thereof. An eccentric pin 38 works in this slot and is mounted in a spiral gear 40 which is arranged to be rotated slowly by a worm wheel 41, this worm wheel being secured fast on the shaft 3.

For an understanding of the details of construction ofthe strainer drum, reference should be made more particularly to Figs. 1, and 5 to 8, inclusive. It will be observed that the wire fabric 15 which forms the strainer element is supported at the inner edges of clamping rings 42- 12, arranged in pairs. Each pair of these rings is circumferentially groovednear its inner margin, asbest. shown in Fig. 7, to receive the fabric and a rod 'or wire 43 which islocated in the groove between cooperating rings. This rod assists in clamping the 'wire fabric securely between the mugs and in stretching the fabric as the ringsfirmly to the clamping ,rings. ing surface of *the drum toward the smaller on each rod immediately beside each of the rings, and by properly manipulating these nuts in a manner which will be obvious from an inspection of Figs. 5 and 6, the rings :12 can be m'ovedaxially of the drum to stretch the wire fabric in an axial direction. The

this lever being operated by a link 35 which 1s plvoted to another lever 36 having a slot .ing ne rings 42-.42' is drawn toward the chanring 13 by a series of bolts, one of which is shownat 47 in Figs. 5 and 8 The wire fabric'15'may consists of a wide web, the width being drum,"and the ends may be brought together and secured in grooves formed in abutting faces of the split ends of the rings, as shown in Figs. 3 and 5, a. rod or wire 48 being used ertia,

in the grooves to assist in clamping the wire in place, just as the rod 443 cooperates with the rings 42. The split sectionsof the rings are drawn together by bolts 50, Fig. 5, to clamp them on the rodand on the fabric. Preferably, also, the ends of the'rings are bevelle'd, as shown at 51; Fig. 5, and the bevelled ends of adjacent rings overlap each other to hold them in contact while'permitting theaxial adjustment of adjacent pairs of rings relatively to each other, as above described.

In order to support the wire fabric 15 against the forces set up by' centrifugal in the clamping rings 42 are provided with flan es 52-52 which bear a ainst the outer surfiice of the fabric, the. fingers of adjacent rings where the project toward each other being staggere as clearly shown' in the drawings, so that relatively short sections only of thefabric are leftunsupported.

It will now be appreciated that the invention provides a drum construction in which the difficulties of handling a wire fabric have been successfully overcome, the drum having a smooth inner surface, which is very desirable, and also having provision for stretching the fabric tightly. At-the same time the expense of manufacturing the drum is withinreasonable limits. By adjusting the valve' 26 or regulating in any other way the pressure of the water or other fluid used to of} feet the movement of the thickened pulp across the straining surface, the rate of such movement can be controlled and the thickness of the layer of thickened pulp maintained on the inner surface of the erned.

The invention thus provides a pulp tl1iekenin machine of unique organization, which can e manufactured ficient, and has a very high capacity in proportion to its size. While a preferred embodiment of the invention has been above described, it will be-understoodthat the invention may be embodied in other forms without departing from the spirit or scope thereof. Also, that the method devised by this invention may be practiced with the aid of a great variety of forms of apparatus.

Having thus described our invention, what we desire to claim as new is:

1. In a machine of the character described,

slip between the right-hand ring' disposed axially of the to move them across the strainer can be gov-' economically, is cfthe combination of a straining surface, means fordelivering pulp in suitable relationship means for directing fluid under pressure against such accumulation to move it across said surface.

2-. In a machine of the character described, the combination of a. tapered rotary strainer drum of approximately circular. cross-section mounted to revolve about an approximately horizontal axis, means for delivering pulp to the interior of said drum whereby liquid constituents of the, pulp will pass through the straining surface and solid constituents will accumulate upon said surface, and means for acting on said solid constituents to move them across the drum toward one end thereof.

, 3. In a machine of the character described, the combination of a tapered rotary straining drum of approximately circular cross-section mounted to revolve about horizontal axis, to the interior of said drum whereby liquid constituents of the pulp will pass through the strainingsurface and solid constituents will accumulate upon said. surface, and

means for acting on said .solid' constituents drum toward the smaller end thereof.

an approximately means for delivering pulp 4. In a pulp thickening machine, the combination of a rotary straining drum, means for delivering pulp to the interior of said drum whereby a part of the liquid therein will pass through the straining surface and the thickened pulp will accumulate on the-said surface. and means for directing one or more jets of fluid under pressure against said thickened 'pulp to move it across said straining surface.

5.- In a pulp. thickening machine, the combination of a rotary straining drum, means for delivering pulp to'the interior of said drum whereby a part ofthe liquid therein thethickened pulp will accumulate on said surface, a scraper for ejecting the thickened pulp from said drum, and means for directagainst said pulp to transfer it across said surface intothe range of-operation of said scraper.

.6. In a pulp thickening machine, the combination of a rotary straining drum, means for delivering pulp to the interior of said drum whereby a part of the liquid therein will pass through the draining surface and the thickened pulp will accumulate on said surface, meansfor directing one or more jets of fluidunder pressure against said thickened pulp to move it across said surface, and means for regulating the rate of advance of said thickened pulp across said surface.

7. In a pulp thickening machine, the comwill pass'through the straining surface and e I 9. In a pulp thickening bination of a rotary straining drum, an inlet bination of a rotary straining drum, means for delivering pulp to the interior of said drum whereby apart of the liquid therein will pass through the straining surface and the thickened pulp .will accumulate on said surface, means for directing a jet of fluid under pressure against said thickened pulp to move it across the straining surface, and means for traversing said jet.

8. In a pulp thickening machine, the combination of a rotary straining drum, means for delivering pulp to the interior of said drum whereby a part of the liquid therein will pass through the straining surface and the thickened pulp will accumulate on said surface, and a spray pipe proj ccting into said drum and having outlet apertures arranged to direct jets of water against said thickened pulp at inclinations serving to move said pulp across the straining surface toward oneend of said drum.

machine, the comspout for delivering pulp to the interior of said drum, and means located substantially at the discharge end of said spout for re gu lating the delivery of pulp to said drum.

10. In a pulp thickening machine, the com bination of a rotary straining drum, an inlet spout for delivering pulp to the interior of said'drum, 'and a gate located substantially at the discharge end of said spout and adjustable tovary the size of the discharge aperture of said spout.

11." In a pulp thickening machine, the combination of. a straining drumof approximately circular cross-section, means supporting said drum for rapid rotation about a substantially horizontal axis, an inlet spout for delivering pulp to the interior of said drum whereby thickened pulp will accumulate on the straining surface of the drum, a pivoted gate located substantially at the discharge end of said spout and adjustable to vary the size of the discharge aperture of said spout, and means whereby said gate may be adj usted while the machine is in operation.

12. In a pulp thickening machine, the combination of a straining drum "of approximately circular cross-section, means supporting said drum for ra id rotation about a substantially horizonta axis, a casing in which said drum is mounted, an inlet spout leading into said drum for conducting pulp into the interior of the drum, a spray pipe projecting into said. drum and having outlet apertures therein for directing jets of water against the thickened pulp on the inner surface of the drum to force it toward one end of the drum, and a scraper cooperating with said drum at the discharge end thereof to eject the thickened pu lp from the drum.

13. In a pulp thickening machine, the combination of a straining drum of approximately circular cross-section, means supporting said drum for rapid rotation about a subsaid drum and having outlet apertures ar ranged to direct jets of water against the thickened=pulp on the straining surface of thedrum to move said pulp across the said surface toward the smaller end of said drum.

14. A straining drum for pulp thickening machines and the like,.comprismg a porous fabric strainer, and supporting means for holding said straincr in. an approximately circular form with the inner surface thereof substantially smooth.

15. A straining drum for pulp thickening machines and the like, comprising a porous fabric forming the straining surface of the drum, and supporting means for said fabric including members adjustable to stretchthe fabric.

16. A straining drum forpulp thickening machines and the like, comprising a wire fabric forming the straining surface of the drum, and supporting means for said fabric including members to which the fabric is attached, said members being adjustable to stretch the fabric axially of-the drum.

17. A straining drum for pulp thickening machines and the like, comprising'a wire fabrioforming the strainingsurface of the drum,

and supporting meansforsaid fabric includmg members to which the fabric is attached, said members being adjustable to stretch the fabric circumferentially.

18. A straining drum for pulp thickening machines and the like, comprising a wire fabric forming the straining surface of the drum, and supporting means for said fabric includmg members adjustable to stretch the fabric both circumfe'rentially and axially.

19. A straining drum for pulp thickening machines and the like, comprising a wire fabric-forming an approximately circular strainer, and supporting means for holding said fabric in its operative position including 'clampingrings grooved to receive said fabric, and, means cooperating with said rings to clamp them on the fabric.

20. A straining drum for pulp thickening machines and" the like, comprising a wire fabric forming an approximately circular strainer, supporting means for holding said fabric in its operative position including clamping rings grooved to receive the fabric, rods cooperating with the fabric to hold it in said grooves, and means cooperating with said rings to clamp them on the fabric and on said rods.

21. A straining drum for pulp thickening machines and the like, comprising a wire fabric forming an approximately circular strain-' er, and supporting means for said strainer in- -cluding a series of rings encircling said .machines and the like,compr1sing a wire fabric forming an approximately circular strainor, supporting means for said fabric including a series of'clamping rings arranged in pairs and encircling. the strainer, said rings clamping portions of the fabric between their inner margins, and means for supporting said rings for axial adjustment .totigliten said fabric. 23; 'A straining drum for pulp thickening machines and the like,'comp'risi ng ja'wire fabric forming an approximately circular strainer, supporting means for said fabric including a seriesof clampingrings arranged in pairs and encirclin'gthe strainer, said rings clamping portions of the fabric between their inner margins, threaded rods extending through said rings, and nuts on said rods for to move it across the straining surface.

adjusting said rings' to tighten the fabric.

24. That improvement in processes of thickening pulp, -which consists in straining surplus. water out of' the pulp, and utilizing the action of fluid against thethickened pulp 25. That improvement in processes of thickening pulp, which consists in collecting the thickened pulp ona straining surface, and moving said thickened pulp across said surface by a jet of fluidunder pressure.

26. That improvement in processes of thickening pulp, which consists in straining surplus water out of the pulp, and directing a plurality of jets of fluid against the thickened pul at inclinations serving to eject it from sal surface.

27. That improvement in ,processes of thickenin 111 which consists 1n strainin c P p: g

. surplus water out of the pulp, directin a jet of fluid under pressure against the thic ened pulp at an inclination serving to move it across the straining surface, and moving said jet to effect a further movement of said pulp across said surface- 28. That improvement in processes of thickening pulp, which consists in producing 'a thickening action centrifugally upon theinner surface of a strainer drum, and forcing the thickened pulp along the straining surface .by .means of fluid pressure directed against said pulp.

29. That improvement in processes of thickening pulp, which consists in flowing a stream 'ofpulp continuously-into a revolving straining drum, rotating-said drum at a sufii-.

cient speed to create centrifugal force serving to propel the surplus Waterin the pulp through the straining'surface and thereby collect the thickened pulp on said surface, and moving the thickened stock across said surface by directin a jet of fluid under pres sure against the pu ip.

30. That improvement in processes of thickening pulp, which consists in-fiowing a stream of pulp continuouslyinto a revolving straining drum, rotating said drum at a suflicient speed to create centrifugal force serving to propel the surplus water in the pulp through the straining surface and thereby collect the thickened pulp on the said surface, utilizing said motion to scrape the thickened stock out of said drum, and directing jets of fluid under pressure against the thickened pulp on said surface to move the pulp:

into position for said scraping action.

31. A straining drum for pulp thickening machines andthe like, comprisinga porous fabric strainer, and supporting means for holding said strainer in an approximately circular form with the inner surface thereof substantially smooth, said supporting means including part-s bearing on the outer surface of the strainer at closely spaced intervals and supporting it a ainst outward distortion.

NTON J. HAUG. RICHARD J HAUG. 

